Subclinical Leaflet Thrombosis Reductions With NOAC Monotherapy Following TAVI Procedures

Article Impact Level: HIGH
Data Quality: STRONG
Summary of  JAMA. https://doi.org/10.1001/jama.2026.17036
Dr. Christopher S. Dodgson et al.

Points

Oslo University Hospital researchers evaluated NOAC monotherapy against ASA monotherapy in three hundred sixty consecutive post-TAVI patients without independent indications for systemic anticoagulation.
Primary efficacy evaluations at twelve months demonstrated that NOAC monotherapy reduced hypo-attenuated bioprosthetic leaflet thickening by forty-five percent compared to aspirin.
Primary safety outcomes proved noninferiority for direct oral anticoagulants across composite endpoints of severe bleeding, thromboembolic events, and all-cause mortality.
All-cause mortality occurred in two patients assigned to NOAC monotherapy compared to ten patients assigned to aspirin monotherapy during the study period.
Severe life-threatening bleeding incidents occurred exclusively within the aspirin arm, supporting NOAC monotherapy as a safe alternative to standard antiplatelet therapy.

Summary

This study evaluated the efficacy and safety of non-vitamin K antagonist oral anticoagulant (NOAC) monotherapy compared to acetylsalicylic acid (ASA) monotherapy in post-transcatheter aortic valve implantation (TAVI) patients without an independent indication for oral anticoagulation. Led by Øyvind Lie at Oslo University Hospital Rikshospitalet and published in JAMA after presentation at the ESC Congress 2026, the ACASA-TAVI trial investigated whether direct oral anticoagulation could prevent bioprosthetic subclinical leaflet thrombosis without elevating major bleeding risks. Given that leaflet thrombus formation contributes to early bioprosthetic valve dysfunction and subsequent thromboembolic events, the trial sought to optimize post-interventional antithrombotic regimens for expanding patient populations.

The randomized trial enrolled 360 consecutive post-TAVI patients aged 65 to 80 years across three Norwegian medical centers, allocating participants 1:1 to 12 months of NOAC monotherapy (apixaban, edoxaban, or rivaroxaban) or ASA monotherapy. Cardiac computed tomography performed at 12 months demonstrated a significant 45% reduction in hypo-attenuated leaflet thickening—the primary efficacy endpoint—among patients receiving NOACs compared to ASA (17.2% vs. 32.6%; risk ratio 0.55; 95% CI 0.37 to 0.82; p = 0.004).

Safety evaluations met noninferiority criteria for the composite endpoint of Valve Academic Research Consortium-3 bleeding, thromboembolic events, and all-cause death at 12 months (7.5% vs. 10.6%; risk difference -3.3%; 95% CI -9.5% to 2.8%; p for noninferiority < 0.001). Overall mortality occurred in two patients in the NOAC arm compared to 10 patients in the ASA arm, with life-threatening and lethal bleeding events limited exclusively to the ASA cohort. The findings demonstrate that post-TAVI NOAC monotherapy effectively reduces subclinical bioprosthetic leaflet thrombosis while preserving clinical safety compared to antiplatelet monotherapy.

Link to the article: https://jamanetwork.com/journals/jama/fullarticle/2853401

References

Dodgson, C. S., Herstad, J., Kløve, S. F., Flygel, M., Akhavi, M., Høie, S., Beitnes, J. O., Eek, C. H., Broch, K., Cunen, C., Gullestad, L., Aaberge, L., Lunde, K., Bendz, B., & Lie, Ø. H. (2026). Anticoagulation monotherapy vs antiplatelet monotherapy after transcatheter aortic valve implant: The acasa-tavi randomized clinical trial. JAMA. https://doi.org/10.1001/jama.2026.17036